In conventional turbomolecular pumps the turbomolecular pump main unit and the control device are structured separately, and thus the cooling mechanism for cooling the turbomolecular pump main unit and the cooling device for cooling those components of the control device that require cooling are provided separately, where the turbomolecular pump main unit and the control device are connected by a cable. This type of turbomolecular pump device has a problem in that two cooling mechanisms are required, and there may be errors in the adjustment of the cable length and in the connections.
Given this, there is a turbomolecular pump device wherein the turbomolecular pump main unit and the control device are integrated, and a cooling mechanism is provided therebetween (Japanese Unexamined Patent Application Publication H11-173293 (“JP '293”)). Doing so enables the cooling mechanism to cool both the turbomolecular pump main unit and the components within the control device that require cooling, making it possible to eliminate a cooling mechanism, and also eliminate a long cable for connecting the two.
However, when the turbomolecular pump main unit and the control device are integrated as in the structure in JP '293, the control device and the cooling mechanism are structured separately and the two are brought into contact, and thus there is a problem in that it is necessary to have two panels, that is, the top surface panel of the case of the control device and the bottom surface panel of the cooling mechanism, at the surface of contact between the control device and the cooling mechanism, and a problem in that there are more components than are necessary.
Furthermore, the turbomolecular pump main unit requires periodic overhaul operations in order to remove foreign materials, and thus when the turbomolecular pump main unit and the control device are integrated, it is necessary to separate the turbomolecular pump main unit and the control device in order to perform the overhaul operations on the turbomolecular pump main unit, and thus there is a problem in that this increases the number of components and increases the labor involved in the overhaul operation. In particular, when the structure is such that the cooling mechanism is attached to the turbomolecular pump main unit and fitted into the control device, as in the invention set forth in JP '293, it is necessary to disassemble the turbomolecular pump main unit and the cooling mechanism after removing the turbomolecular pump main unit and the cooling mechanism from the control device, increasing the amount of work involved in the overhaul operations.
In addition, when fitting into the control device after installing the cooling mechanism into the turbomolecular pump main unit, as described above, it is necessary, in the assembly process of the turbomolecular pump device, to have a process for installing the cooling mechanism into the turbomolecular pump main unit, and thus it is not possible to assemble the turbomolecular pump device using the same processes as in the past. That is, when manufacturing both turbomolecular devices wherein the turbomolecular pump main unit and the control device are structured separately, and turbomolecular pump devices wherein the turbomolecular pump main unit and the control device are integrated and a cooling mechanism is provided therebetween, being able to use a common turbomolecular pump main unit would contribute to cost reductions and simplification of operations; however, when the cooling mechanism is attached to the turbomolecular pomp, it is not possible to use a common turbomolecular pump main unit.
Furthermore, because the cooling by the cooling mechanism is through the top surface panel of the case of the control device, rather than the components requiring cooling in the control device, such as transistors, and the like, contacting the bottom surface panel of the cooling device directly, there is a problem in that the cooling efficiency is low.